Facebook terminated its contract with Definers Public Affairs following a bombshell New York Times investigation that detailed how Facebook hired the Republican opposition researcher to counter criticism of its role in spreading Russian misinformation and exposing its users to the political-ad-targeting firm Cambridge Analytica.

The Times says Facebook staff were aware in spring 2016, more than a year before making the disclosures public, that Russian hackers used the platform to interfere with the 2016 presidential election and that CEO Mark Zuckerberg and COO Sheryl Sandberg decided to publicly downplay concerns about interference even as Facebook staff uncovered the extent of the operation. When Facebook finally revealed, in the fall of 2017, that a Kremlin-linked operation had reached nearly 150 million users with false posts in an effort to sway the 2016 election, Facebook launched an intensive lobbying and PR campaign to minimize criticism.

Measures taken by the company included hiring external firms like Definers. Led by political veterans who have worked and campaigned for Republican lawmakers such as Mitt Romney and Marco Rubio, the firm released materials linking a group advocating the breakup of Facebook with billionaire George Soros and published negative articles about other tech companies, like Google and Apple, on its conservative news affiliate NTK Network, said the Times.

Facebook’s employment of Definers was public. The details of the public relations campaign and the lobbying efforts by Sandberg weren’t well known, however.

Backlash was quick. Patrick Gaspard, president of Soros’ Open Society Foundation, shared a letter he wrote to Sandberg on Twitter late Wednesday criticizing the company for attacking Soros.

Zuckerberg said Thursday in a conference call with reporters that he didn’t know about Definers until he read the Times article. Sandberg similarly denied that she knew Facebook hired the firm.

"I did not know we hired them or about the work they were doing, but I should have," she wrote in a Facebook post Thursday night. The firm didn’t respond to a Forbes request for comment.

The firm’s expansion to Silicon Valley in 2017—headed by Tim Miller, former communications director for Jeb Bush—was conveniently timed with the beginning of Facebook’s storm. Miller toldRecode in July 2017 that the company’s philosophy is to “have positive content pushed out about your company and negative content being pushed out about your competitor.”

The Times investigation lays out how Definers took on this strategy with Facebook. Articles on its affiliate NTK Network downplayed the effect of Russian meddling on Facebook. “Russian Content on Facebook Amount to Just .004% of Total Content,” one headline from October 2017 read, while another headline from earlier that month read, “Majority of the Russian-Bought Facebook Ads Appeared After 2016 Election.” Definers President Joe Pounder is listed as editor in chief of the site.

Facebook amped up its relationship with the PR firm after the Times, in an investigation earlier this year, exposed how Facebook was aware that a political ad targeting firm that had worked for the Trump campaign, Cambridge Analytica, had accessed the personal data of as many as 87 million Facebook users, without their consent. A document circulated to reporters by Definers this summer painted Soros, a frequent target of anti-Semitic campaigns from the far right, as the figure behind widespread anti-Facebook sentiment. The firm encouraged reporters to explore any potential financial relationships between Soros and organizations within the Freedom from Facebook activist group, like civil rights advocacy organization Color of Change.

In a statement to Forbes on Thursday, Facebook confirmed that Definers encouraged reporters to explore the funding of Freedom from Facebook. “The intention was to demonstrate that it was not simply a spontaneous grassroots campaign, as it claimed, but supported by a well-known critic of our company,” the statement says. “To suggest that this was an anti-Semitic attack is reprehensible and untrue.” The company also denied in the statement that it paid Definers to write articles on Facebook’s behalf.

Color of Change called for the firing of Joel Kaplan, Facebook’s vice president for corporate public policy.

“By suggesting to reporters that Color of Change is acting as the puppet of Mr. Soros merely because he is one of our many funders, they have given oxygen to the worst anti-Semitic conspiracy theories of the white nationalist Trump base,” wrote Color of Change president Rashad Robinson in a statement. “Those theories aim to not only dehumanize Jews, but also seek to deny legitimacy to progressive social movements led by people of color, by suggesting we have no agenda of our own.”